I was left without the GRUB bootloader. In order to restore GRUB, I started with the Debian Lenny business-card CD in the "rescue" mode. All I want to do is reinstall GRUB, and I'm being asked all kinds of questions about my drives, how I want them formatted, waiting for the base system to install ... I got out of there quick. I didn't want to screw up my current Lenny install, which I'm actually relying on heavily at the moment.